White Goods

White goods is the trade term for major electrical household appliances that wash, dry, rinse, cool or cook. The name comes from the white enamelled sheet steel that clad the first appliances and today applies regardless of colour: a stainless steel refrigerator or a black oven counts just the same. Every one of these appliances contains a motor, a heating element or both, and at each of those points an insulating part separates voltage from sheet metal and water. GOBA, a manufacturer of insulating parts since 1959, produces these parts for manufacturers of household appliances. This article shows which appliances belong to the group, where the line to brown, red and grey goods runs, and what white goods contain from the supplier's point of view.

Which appliances count as white goods?

The German dictionary DWDS defines white goods as technical appliances for kitchen and household that are frequently offered in white, and lists Weißware as a synonym. In German retail the forms Weißwaren and Weißgeräte circulate as well, all meaning the same thing. The group includes:

• washing machines, tumble dryers and washer-dryers
• dishwashers
• refrigerators, upright freezers and chest freezers
• cookers, ovens, hobs and induction hobs
• extractor hoods

A second, older meaning refers to undyed white textiles made of cotton or linen. It hardly plays a part in current usage any more, but the DWDS still lists it as the first meaning. In retail and in the supply industry, white goods always means the household appliance.

Small appliances such as coffee machines, toasters, vacuum cleaners or hair dryers do not, strictly speaking, belong to the group. Retail lists them separately, although some retailers count them as white goods anyway. For engineering the distinction matters more than for retail, because the safety standard tests an unattended major appliance more severely than a small appliance someone holds in their hand. More on that in the section on standards.

White goods, brown goods, red goods and grey goods compared

Retail has sorted electrical appliances by colour for decades, and each colour goes back to the housing that the respective appliance group once had. Wikipedia lists four groups.

The boundaries blur, and a television with internet access is brown and grey goods at once. For the supplier a different boundary counts: white goods operate with mains voltage, water, heat and moving masses inside the same housing. No other appliance group places so many demands on the insulation at the same time.

Which insulating parts are inside white goods?

Every major household appliance has three places where insulating materials work: in the motor, at the heating element and around the electronics. Added to these are separating layers between assemblies, nonwovens against vibration and protective films. The table below assigns them to the appliances.

The assignment draws on our production for washing machines, dishwashers and refrigeration appliances and on the documentation of mica and drive manufacturers (Asheville Mica, Elmelin, Hanning). It is typical rather than complete, because every appliance manufacturer has its own assemblies. Two patterns run through every row, though. Wherever a motor runs, sheet insulation works in the slot, which is the core of our insulation materials in classes A to C. Wherever a heating element sits, mica takes over, because no organic material withstands the continuous heat directly at the heating wire.

Motor insulation in washing machine, dryer, dishwasher and refrigerator

The drive motor of the washing machine is the most heavily stressed insulation system in the entire appliance. It alternates between slow washing and spin cycles at 1,400 or 1,600 drum revolutions per minute, sits beneath the damp tub and runs several thousand hours over the life of the appliance. Two motor types share the market: the classic universal motor with commutator and brushes, and the brushless DC motor (BLDC) with inverter that has been standard in the upper efficiency classes for years. Both need the same sheet insulating parts.

• Every slot of the lamination stack receives slot insulation that separates the winding from the earthed iron. In the washing machine it is usually a laminate of polyester nonwoven and PET film (DMD) or a PET-Nomex composite (NMN), creased and pushed into the slot with a pre-embossed edge.
• After winding, a slot wedge closes the slot and holds the wires in the lamination stack, even when the drum spins out of balance.
• In the end winding, the phase insulation separates the coils of different phases, where steep inverter edges meet in a confined space in BLDC motors.
• The universal motor adds armature insulation and commutator insulation, because its rotor is wound as well.

The thermal class of these parts follows IEC 60085. Class B at 130 °C is the lower limit for appliance motors, class F at 155 °C the usual state of the art, and in dryers or near heaters the design moves to class H at 180 °C. Which materials correspond to which class is covered in the article on thermal classes of insulation. For the structure of the winding itself, the pillar article on the electric motor winding leads the way.

Pumps are small motors with the same parts, but in water. The circulation pump of the dishwasher now often carries the heater inside the pump housing, and Hanning supplies such heated circulation pumps in series. That puts the motor insulation next to a heating element and in splash water at the same time, and the material group by CTI becomes a design parameter. The compressor in the refrigerator is the opposite: little heat, but slot insulation permanently in refrigerant and oil, so chemical resistance comes before thermal class.

Heating elements and high temperature: oven, dryer, induction hob

At the heating element the use of plastic film ends. The heating wire of an oven, a dryer heater bank or a toaster lies on or in a carrier that withstands the temperature of the wire and at the same time insulates it from the sheet metal. That carrier is mica, either as a natural mica plate or as mica composite, meaning mica with a resin binder. Asheville Mica describes the heater plate for toaster element cards and the ceramic and mica standoffs for nichrome heating coils in dishwashers, dryers and ovens in exactly this way. Elmelin supplies rigid mica plates from 0.10 to 50 mm thick with heat resistance up to 1,000 °C and names hair dryers, toasters and tumble dryers as applications.

Between the heating zone and the motor, aramid paper and polyimide film do the work. Nomex carries 180 °C continuously, polyimide film such as Kapton 240 °C. Both insulate the terminal compartment behind the oven, the wiring harness along the heater bank or the fan motor of the convection blower. Which materials still qualify above that is classified in the article on high-temperature insulation.

The induction hob is the special case among cooking appliances, because no heating coil works there. Beneath the glass ceramic lies a coil of high-frequency litz wire operated at 20 to 30 kHz, with a ferrite yoke underneath. A patent from 1995 (US 5430273 A) describes, between coil and glass ceramic, an insulating plate of pyrogenic silica aerogel that keeps the heat of the pan base away from the coil, and litz wires with 0.2 mm single-strand diameter. The coil needs mica or polyimide as a carrier, and the power electronics below need insulating films with high dielectric strength in a small space.

Which standards apply to insulating materials in white goods?

The safety standard for all household appliances is IEC 60335-1, adopted in Europe as EN 60335-1 and in Germany as VDE 0700-1. It applies to appliances with a rated voltage up to 250 V single-phase and 480 V otherwise. Each appliance type has a Part 2 with particular requirements: 60335-2-5 for dishwashers, 2-6 for cookers, hobs and ovens, 2-7 for washing machines, 2-11 for tumble dryers, 2-24 for refrigerators and freezers and 2-31 for extractor hoods. For insulating parts four clauses of the standard decide, and the figures in them determine which material qualifies at all.

The distinction between attended and unattended is the point that separates white goods from small appliances. A vacuum cleaner or an iron runs while someone stands next to it. A washing machine runs at night, a refrigerator around the clock, a dryer on a delayed start. For these appliances the standard demands the higher glow wire level from 0.2 A upwards, and the tightened values have applied since February 2007, which elektronikpraxis described at the time as a changeover for connection technology. A separating layer of PET film that sits at a motor terminal falls under this rule because it lies within 3 mm of the connection.

The creepage distances depend on the CTI value of the material per IEC 60112, explained in the article on surface leakage current. For fire behaviour the classification per UL 94 applies alongside, whose V-0 and V-1 the standard accepts as a substitute for the small-part test. The thermal class of the winding is checked in the heating test of the standard by the resistance method: winding resistance measured cold and warm, temperature rise calculated from it, with a limit that depends on the thermal class. Anyone who picks the class too tightly fails at this point.

Energy label and ecodesign: what changes for motor and insulating material

Since 1 March 2021, refrigerators, washing machines, dishwashers and televisions have carried the new EU energy label with the A to G scale. The German Environment Agency describes the consequence: an appliance that previously carried A+++ lands in B, C or D on the new label, and class A was deliberately left empty at launch so that manufacturers have to keep gaining efficiency. In parallel, the ecodesign regulations oblige manufacturers to keep spare parts available for 7 to 10 years after the last unit is placed on the market and to design them so that they can be replaced with commonly available tools.

For insulation this has three consequences that no consumer notice mentions:

1. Efficiency comes from the motor. The BLDC motor with inverter is displacing the universal motor because it runs without brush losses and sets speed freely. It needs more copper in the slot, and the slot insulation gets thinner so that the fill factor rises. Converters explicitly describe the trend towards ever thinner slot liners, and that step only works with a material that holds the same dielectric strength at lower thickness.
2. The inverter switches with steep edges. The turn and phase insulation sees voltage spikes that did not exist with the universal motor on the mains. The design rules for inverter-fed motors, partial discharge resistance and clean phase separation in the end winding, therefore apply to appliance motors as well, which used to get by with class B on the mains.
3. The spare parts obligation extends the life cycle of the insulating part. A slot liner that goes into series production in 2026 must remain deliverable in identical form well into the 2030s. Documented materials, archived tooling and a production that can rerun small batches become purchasing requirements.

Our recommendation to design engineering is therefore to base the thermal class and the thickness of the slot insulation on the next label step, not on today's motor. Anyone who designs class F today where class B would still suffice on paper has headroom for the next efficiency level without rebuilding the tool.

What GOBA produces for manufacturers of white goods

GOBA supplies insulation materials and finished insulating parts for motors, heating elements and controls in washing machines, dishwashers, refrigerators and small appliances. The industry page on household appliances lists the assemblies: stamped parts and laminate blanks for motors, heaters and electronics, laminated film composites for combined thermal and electrical separation, nonwoven materials for vibration damping in pumps and fan modules, and special films with high dielectric strength for compact control units and power modules. Production runs in series and small batches to DIN ISO 2768 and ISO 9001, on request from R-PET variants that can be recycled.

The material stock covers thermal classes A to C: pressboard for class A, polyester film, DMD laminate and polyester nonwoven for class B, NMN laminates for class F, Nomex 410, 411 and 414 plus NKN laminates for class H, and Kapton polyimide film for class C. All branded products are UL listed, and for polyester film we are the largest European converter of Mitsubishi Hostaphan in the heavy-gauge range.

In stamping we process material thicknesses from 0.023 to 3.0 mm, with parts up to 1,000 x 2,000 mm. For slot liners and slot wedges we pre-emboss the fold line in the same stamping stroke so that the part stays in its final position on your assembly line; tool choice and process are described under stamping and forming. We deliver insulating parts stacked or packeted for automated processing, in individual customer projects with marker lines that your sensors detect during assembly. More on moulded parts with creasing, embossing and flanging is available under insulating and moulded parts.

For winding machines and cable wrapping we shear-slit roll stock into widths from 5 to 1,600 mm with a width tolerance of plus minus 0.1 mm, wound onto cores of 25, 55, 76 or 152 mm inner diameter. The same applies to your own roll stock, see contract slitting. The round core insulation of the wiring harness itself is not something we make; the distinction is explained in the article on cable insulation.

Objection: the motor arrives complete from the drive manufacturer

Purchasing at the appliance manufacturer sources the motor complete from Hanning or another drive manufacturer and never sees slot insulation on its bill of materials. That is true, and it changes little. First, an insulating parts manufacturer such as GOBA produces exactly the parts the drive manufacturer builds into the motor, and the requirements from IEC 60335-1 reach us through the motor specification. Second, enough remains inside the appliance that the appliance manufacturer is responsible for itself: the separating layer behind the control board, the mica plate at the heater bank, the insulating film in the terminal compartment, the nonwoven beneath the pump, the protective film on the stainless steel front. These parts are small on the bill of materials and expensive when they fail, because a material change triggers the glow wire test on the appliance again.

Our position is clear: anyone building a household appliance for the spare parts obligation of the next ten years should write the insulating material into the drawing with material name, thickness, thermal class and glow wire rating, rather than leaving it to the supplier as free text. A material change that saves three cents in purchasing costs many times that at the next type test.

GOBA Takeaway

White goods is a colour in retail and an insulation system in engineering. Motor, heating element and electronics share a housing with water and heat, and IEC 60335-1 sets the limits: 125 °C ball pressure, 750 °C glow wire from 0.2 A, creepage distances by CTI. The energy label drives the motor towards BLDC and the slot insulation towards thinner laminates with a higher thermal class. Anyone who knows these figures when choosing the material orders the insulating part right the first time and beyond the spare parts obligation.

We have produced insulating parts since 1959, stamped, creased and slit to your drawing. Send us material, thickness, thermal class and quantity via the page on household appliances, and for special constructions and small batches via custom products.

FAQ on White Goods

What is the difference between white goods and brown goods?

White goods are major household appliances that wash, rinse, cool and cook. Brown goods are consumer electronics such as televisions, radios and hi-fi systems. The name brown goods comes from the wooden cabinets of early radio sets, the name white goods from the white enamelled sheet steel of the first washing machines and refrigerators. Alongside them, red goods covers heaters and grey goods covers computers and communication technology.

Are vacuum cleaners and coffee machines white goods?

Strictly speaking, no. Vacuum cleaners, coffee machines, toasters and hair dryers are small appliances and form their own group in retail, even though some retailers count them as white goods. Technically the distinction is clearer: the safety standard IEC 60335-1 tests a small appliance that someone attends less severely than a washing machine or refrigerator that runs unattended.

Which standard applies to insulation in household appliances?

IEC 60335-1, in Europe EN 60335-1 and in Germany VDE 0700-1, with a Part 2 for each appliance type. For insulating materials it sets the ball pressure test at 125 °C for parts supporting live parts, the glow wire test at 750 °C at connections above 0.2 A in unattended appliances, and the creepage distances by CTI value and pollution degree. The thermal class of the winding follows IEC 60085.

Which thermal class does a washing machine motor need?

Class B at 130 °C per IEC 60085 is the lower limit, class F at 155 °C the usual state of the art for BLDC motors with inverter. In tumble dryers and near heating elements the design moves to class H at 180 °C. Polyester film or DMD laminate is sufficient for class B, an NMN laminate with Nomex for class F, and Nomex paper or an NKN laminate with a polyimide core layer for class H.

Why is there mica in ovens and dryers?

Because the heating wire lies directly on its carrier and that carrier has to withstand the wire temperature. No organic insulating material manages that permanently, whereas mica and mica composite stay stable above 500 °C and insulate electrically at the same time. That is why the heating coils of ovens, dryer heater banks and toasters sit on mica plates or mica standoffs, while polyester film, Nomex and polyimide work in the cooler terminal compartment and in the motor.